It has been previously proposed to design and construct stringed instruments, such as, acoustic guitars in such a way that they can be broken down for ease of carrying or handling. For example, in my prior U.S. Pat. No. 4,686,882 entitled "EXPANDABLE AND COLLAPSIBLE ACOUSTIC GUITAR", hinged wing portions can be expanded away from a guitar body to form a sound chamber with the body, and a neckpiece along with the wing portions are foldable over the body to form a compact unit when not in use. Although this basic construction is very useful, it does possess certain limitations with respect to durability of construction and tonal characteristics particularly with guitars and other musical instruments having large sound chambers.
Among other problems associated with collapsible stringed instruments and especially those which employ sound chambers composed of wood, fiberglass or plastic materials is a tendency to become warped or misaligned under repeated use or when subjected to different temperature and humidity conditions. Furthermore, it has been found that the sound chamber when expanded should be fully enclosed and not subject to air leakage between the moving parts of the sound chamber. For example, referring to my earlier patent, it was found that the collapsible wing sections of the guitar should contain a fairly tight air and vibration-conducting seal with the central portion or body for most effective development of the proper sound or tonal characteristics but at the same time be capable of being retracted or folded together over the body when in the collapsed position.
It is therefore proposed to provide for an improved collapsible sound chamber which is adaptable for use in various stringed musical instruments and which is capable of being disassembled into a compact unit for ease of storage and handling.